1. Field
Aspects of embodiments of the present invention relate to a liquid crystal display device.
2. Description of the Related Art
With the trend toward lighter and slimmer displays, including portable display devices such as notebook computers, mobile phones, or portable media players (PMPs) as well as home display devices such as TV sets or monitors, a variety of flat panel displays are widely used. There are a wide variety of flat panel displays, including liquid crystal display devices, organic electroluminescent display devices, electrophoretic display devices, and so on.
Among the flat panel displays, liquid crystal display devices include a liquid crystal layer containing liquid crystal molecules. The arrangement of the liquid crystal molecules varies according to the voltage applied to the liquid crystal layer, and the light transmittance of the liquid crystal layer varies accordingly. An example liquid crystal display device includes a plurality of pixel areas that display a desired image by controlling the voltage applied to the liquid crystal layer included in each of the pixel areas. Each such liquid crystal layer may serve as a capacitor, which will hereinafter be referred to as a liquid crystal capacitor. Thus, the liquid crystal display device displays a desired image by controlling the voltage applied to both ends of the liquid crystal capacitor.
The liquid crystal display device is a switching device for applying a voltage to the liquid crystal capacitor and may employ a thin film transistor. Kickback voltage may be generated due to parasitic capacitance formed between a gate and a drain of the thin film transistor. If kickback voltage is generated, the voltage applied to the liquid crystal capacitor varies, resulting in flicker or image sticking in the image displayed on the liquid crystal display device. For example, in a liquid crystal display device in which the polarity of a data voltage is inverted at 60 Hz, there is a difference in brightness between an odd-numbered frame and an even-numbered frame due to kickback voltage, resulting in flicker of 30 Hz. In addition, if the liquid crystal display device is continuously driven when kickback voltage is generated, a DC offset is applied to the liquid crystal layer, which may change light transmittance of the liquid crystal layer, thereby resulting in a residual image.